Field of the Invention
The present invention relates to a control unit for height adjustment of a bicycle seat post and, more particularly, to a control unit that requires fewer elements and is easily assembled.
Description of the Prior Art
A height adjustment device of a bicycle seat post is capable of adjusting the height of the bicycle seat post so as to manage the height position of the seat fixed on the top end of the seat post. A control mechanism is used to control the height adjustment device of the bicycle seat post to work or stop. The control mechanism is connected with one end of a wire. Generally, the other end of the wire is fixed to the bicycle handlebar and coupled with a pulling member. When the pulling member is pulled, the wire may drive the control mechanism to push a pin within the height adjustment device of the bicycle seat post to axially move upwards to unlock the oil hydraulic valve inside the height adjustment device of the bicycle seat post to allow the height adjustment device to work. Thus, the seat height position can be adjusted. When the pulling member is released, the pin returns to its home position and the valve locks again. Thus the height adjustment device of the bicycle seat post stops working so as to stop adjusting the seat height and the seat position is secured.
A prior art control mechanism for a bicycle seat post, as disclosed in Taiwan Patent 104200535 and U.S. patent application Ser. No. 14/604,798, comprises a body and a linkage unit. The linkage unit is provided with a pull-down member at the lower portion and a push-up member at the upper portion. The middle section of the pull-down member and the middle section of the push-up member are eccentrically pivoted with the body by a pivot pin respectively. One of the push-up member and the pull-down member provides a connecting pin arranged to a first end where the push-up member and the pull-down member are near each other, and the other one of the push-up member and the pull-down member provides a sliding slot arranged at the first end where the push-up member and the pull-down member are near each other. The opening of the sliding slot is larger than the external diameter of the connecting pin. The connecting pin may pass through the sliding slot. Thus, the push-up member and the pull-down member are combined together with the connecting pin and the sliding slot. The pull-down member is provided with a control end for connecting a controlling wire. The push-up member is arranged with a push-up end under a main pin of the height adjustment device of the bicycle seat post. When the controlling wire is pulled, the push-up end drives the main pin to move upwards so as to direct the height adjustment device of the bicycle seat post to work. The prior art control mechanism for a bicycle seat post is controlled by the controlling wire via the linkage unit. The linkage unit includes the push-up member, the pull-down member, the two pivot pins, and the connecting pin. The prior art control mechanism needs many assemblies and consumes more working time in assembling. It is against the background and the drawbacks associated therewith that the present invention has been developed.